Planform change and Fundulus SNP data for small watersheds in South Mississippi and Louisiana

Fluvial geomorphic processes and the resulting patterns of landform morphogenesis affect the distribution and connectivity of habitat patches for aquatic organisms. Human alterations to fluvial geomorphic processes may affect local habitat quality and stability, and affect connectivity of habitat patches by altering the distribution, supply, and movement of landform-generating materials. This dataset examines 17 watersheds in south Mississippi and southeastern Louisiana and was used in preparation of a manuscript addressing the hypothesis that elevated planform movement, indicative of advanced fluvial erosion, would cause fragmentation among populations of a headwater specialist (Blackspotted Topminnow Fundulus olivaceus). The dataset includes numerous spatial features derived from the NHD+ dataset used in planform measurements, spatial features digitized from NAPP and NAIP aerial imagery measuring planform characteristics and dynamics, additional metrics of each watershed, and a popula..., Fluvial geomorphic measurements were collected using a remote-sensing approach with QGIS (open-source) geospatial software and National Aerial Photogrammetric Program (NAPP, 1995-1998) and National Agricultural Imagery Program (NAIP, 2019-2020) aerial imagery. River mainstems (>100km2 drainage area) were subsampled at 1km intervals with a stratified random approach (3km sampled per 10km of stream). Planform metrics used to estimate planform characteristics or dynamics (i.e., unvegetated channel width and centerlines) were digitized for each sampled reach in each time period (1990s and 2020s) and exported as shapefiles. Associated watershed metrics pertinent to gene flow were extracted directly or calculated from the NHD+ dataset (e.g., watershed size), or the National Land Cover Database 2019 dataset. Blackspotted Topminnows were sampled from multiple localities per watershed by standard fish sampling techniques. Fin clips were taken in the field, and DNA was extracted and sequenced...., , # Planform Change and *Fundulus* *olivaceus* SNP Data for Small Watersheds in South Mississippi and Louisiana

[https://doi.org/10.5061/dryad.nzs7h44xg](https://doi.org/10.5061/dryad.nzs7h44xg)

###### Principle Investigator Contact Information

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Name: Loren Stearman
Institution: University of Southern Mississippi
Email: [e-mail]
```

###### Alternate Contact Information

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Name: Jake Schaefer
Institution: University of Southern Mississippi
Email: [e-mail]
```

## Dataset Overview

This dataset contains the data and code required to replicate analyses in Stearman and Schaefer (in review), testing the hypothesis that the rate of geomorphic activity in a river, as inferred from planform dynamics, affects the rate of gene flow among populations of a headwater specialist, Blackspotted Topminnow (Fundulus olivaceus). Data cover 17 watersheds in southern Mississippi and southwest Louisiana. Geospatial data include planform metrics (channel widths and centerline...